Manager Joe Girardi #28 of the New York Yankees looks on before a game against the Minnesota Twins at Yankee Stadium on Monday, Aug. 17, 2015. Photo Credit: Jim McIsaac

The dawn of September is an oasis after a grueling five-month stretch for major-league baseball teams. Rosters are permitted to expand from 25 to 40 players on the first of the month, giving managers additional flexibility.

But through manipulation and foresight, Joe Girardi has been able to stretch the limits of his roster even before September.

Case in point: utilizing a sixth starter, such as Bryan Mitchell Monday night against the Twins, although that didn't turn out well for the rookie.

"Our thought process was we didn't use anyone Saturday out of the bullpen," Girardi said before the game. "We didn't use a whole lot on Sunday, so this might be as fresh as our bullpen's going to be in the next couple of days. So let's do it today."

As it turned out, having a fresh bullpen was paramount. Mitchell was struck in the face by a line drive by Eduardo Nuñez, suffered a small nasal fracture and exited in the top of the second.

Monday night's beneficiary, CC Sabathia, was asked if he minded having his start pushed back a day.

"I never do," he said. "Joe just wanted to give guys an extra day. We've had a bunch of games on the road."

Going forward, a lot of it will boil down to how the starters feel and fare, Girardi said.

Masahiro Tanaka, who threw 112 pitches in a complete-game win his last time out against the Blue Jays, has averaged just over 100 pitches in his last seven starts. Ivan Nova injured his right index finger while reaching for a comebacker in his last start against the Jays.

"I know we have another long stretch," Girardi said. "All depends on how hard the starters are worked and how they're feeling at the time that we decide if we need a sixth starter. I just kind of felt with the way we've pushed Nova and Tanaka, and Nova taking that ball off his finger, even though I don't really think it affected him a whole lot, I just thought the extra day would probably help, him being a Tommy John guy."

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Another example is Michael Pineda, who likely will need one more start for Double-A Trenton to rehab a right forearm strain before returning to the big-league rotation.

"Sometimes," Girardi said, "things are based on need."

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